Stool



1935- J. A. CAMPBELL y 2,010,290

STOOL Filed Jan. 7, 1953 3 Sheets-Sheet 1 1 1526055. I i CZ Ccvr ZeZZ-Aug. 6, 1935. J. A. CAMPBELL STOOL Filed Jan. '7, 1933 3 Sheets-Sheet 2mas c2. cwgpzfzz 1935- J. A. CAMPBELL 2,010,290

STOOL Filed Jan. 7, 1935 3 Sheets-Sheet 3 iv, //I i W m 0 0'0 ZflzfzzeaaJcE/vzea CZ. (6277505612 Patented Aug. 6, 1935 UNITED STATES 2,010,290s'roor.

James A. Campbell, Kewaunee, Wis, assignor of one-half to Charles '1.Campbell, Kewaunee,

Wis.

Application January 7,

10 Claims.

The invention relates to improvements in supports for stools, chairs,tables and similar articles, More particularly the invention relates toimprovements in supports for stools, chairs or the like wherein thelength of the pedestal or seat supporting members are extensible withinpredetermined limits in combination with means for automatically lockingsuch members against possibility of collapseunder their weight or theweight of an occupant thereof.

It is an object of the invention to provide an improved extensiblesupport for stools, chairs or the like.

Another object of the invention is the provision of improved lockingmeans for. extensible supports of the kind described, said means beingoperable to prevent decreasing the length of the support under load andyielding under tension to permit further extension of the supportbetween predetermined limits. 3

A further object of the invention is the provision of improved fasteningmeans for extensible supports of the kind described.

A still further object of the invention is the provision of improve-dmeans for locking extensible supports against collapse under compressionexerted thereon and which will permit extensibility of the support undertensile force applied thereto when in normal vertical, inverted, or anyintermediate position.

Many other objects and advantages of the construction herein shown anddescribed will be obvious to those skilled in the art.

To this end my invention consists in the novel construction, arrangementand combination of parts herein shown and described, or uses mentioned.

In the drawings, wherein like reference charaoters indicate like orcorresponding parts:

Fig. 1 is an elevational View of a stool embodying the rinciples oi theinvention;

Fig. 2 is a perspective view of another form of stool embodying theinvention;

Fig. 3 is a longitudinal sectional view through the device shown inlooking position;

Fig. 4 is a View similar to Fig. 3 with the looking portion in releasedposition;

Fig. 5 is a sectional view along the line 5-5 of Fig; 3;

Fig. 6 is a sectional view along the line 66 of Fig. 3;

Fig. 7 is a perspective view of an element forming a portion of thelocking device; 1

Fig. 8 is a view of a fragmentary portion of an alternative embodimentof the invention;

1933, Serial No. 650,687 (01. 94

Fig. 91s a fragmentary sectional view of another form of the invention;

Fig. 10 is ,a View along the line Ill-l0 of Fig. 9.; and

Fig. 11 is a View along the line I I| I of Fig. 9.

Referring now more particularly to the drawings, the numeral l8designates a seat and the numerals l2 and I5 respectively designate theouter and inner telescoping members of an extensible support for theseat. The stool shown in Fig. l is supported by a single extensiblepedestal wherein the member I2 is preferably fastened to the floor by abase member l3 and bolts Hi. The inner member comprises a. locking rodl5 telescopically mounted in a locking box or housing 2i sin-mountingthe member 12. The member [2 is preferably cylindrical and the rod [5extends substantially the full length thereof when the support iscontracted to minimum height. The seat ill is fixedly mounted on therod- IS, the latter ,being provided'for that purpose with a stem IE onits upper end which projects through an opening in a member I! formingthe bottom of the seat. The end portion of the stem i5 is upset to forma riveted connectionof the stem with the member H, such connectionserving to fixedly fasten the seat to the rod IS.

The locking boxor housing 2| has its lower end portion interiorlythreaded for connection with an exteriorly threaded stem 22 projectingfrom the member l2. The upper portion of the housing 2| has its innerperiphery beveled as shown to provide a frusto-conical. chamber 29. Theupper end of the housing 2| is closed by a cap 24, preferably formed ofsheet metal or the removal from the housing but yields sufliciently L topermit removal by the application of force for that purpose. A pair ofoppositely positioned grooves l8 extend the full length of the rod l5for a purpose hereinafter more particularly described. The cap 24 isprovided with inwardly projecting key members 21 which close the slotsfor all extended and retracted positions of the rod l5, therebypreventing the possibility of articles dropping in or being insertedinto the chamber 29 which might clog orotherwise interfere with theproper operation of the looking or retaining mechanism located in thechamber.

The inner periphery of the housing is shown as cylindrical adjacent tothe beveled periphery 28 to provide a cylindrical surface having adiameter somewhat greater than that of the rod l5 extendingtherethrough. The diameter of the inner periphery of the housing 2| issubstantially reduced at the lower end of the surface 36, therebyproviding a shoulder 3i and below the shoulder for a short distance, thehousing has an inner periphery 32 of a still smaller diameter providinga close sliding fit for the rod HE. A lug 20 projects from theperipheral sur-- face 32 into a groove H9 in the rod 95' and provides akey preventing rotation of the rod relative to the housing 2!. Thegroove i9 is so positioned and of such a length as to permit thenecessary telescoping movement of the rod i5 relative to the housing 2iand the member E2. The rod 95 has a diameter slightly smaller than thatof the inner periphery of the member l2 and near its lower end isprovided with an annular groove 4G in which an expansible spring band Mis mounted. The frictional contact 01' the band ll with the innerperiphery of the member I? is such as to require substantial force tomove the rod 55 relative to the member 52 and thereby permits the stoolto be lifted and carried by grasping the seat without movement of therod in the member l2; the weight of the housing 2i, member 52 and thesupporting base i3 being insufiicient to overcome the resistance due tothe frictional contact of the band M with the inner surface of themember l2.

Means is located in the chamber 29 for retaining the rod it lockedagainst downward movement in all extended positions up to the maximumand which permits extension of the support by movement of the rod l5outwardly. The retain ing means comprises a spring band or collar 33located with its upper end in the chamber 29 and its lower end insliding fit with the cylindrical surface 39 of the housing. The collar33 is shown in perspective in Fig. '7 as comprising a cylinder out alongthe longitudinal line 43. The collar 33 normally has a slightly largerdiameter than that of the peripheral surface 39 and is slightlycontracted when mounted therein. The tendency of the collar 33 to expandprovides frictional contact with the surface 39 suiiicient to requiresubstantial force to move the band longitudinally of the housing.

A plurality of recesses 34 are provided in the upper end of the collar33, each providing a seat for one of a plurality of ball bearings 36.The bottoms of the recesses 3 are inclined slightly downwardly andinwardly towards the rod 55 and the spacing of the collar 33 from therod is such that gravity causes the balls to ride in the recesses inpoint contact with the rod. The lower end of the collar 33 has inwardlyturned lugs or keys 35 extending into the oppositely positioned groovesin the rod l The balls are held in their position of contact with therod 15 by a ring washer 3'! resting against and held in position on thetops of the balls by a compressive spring 38. The compressive forceexerted by the spring 38 is less than the resistance of the collar 33 tomovement by reason of its frictional contact with the cylindricalperipheral surface 39.

The position of the collar 33 as shown in Fig. 3 is such that the balls35 are in contact both with the rod i5 and the beveled surface 28 of thehousing 2!, in which position the balls lock the rod l5 against movementinwardly of the housing but permit movement outwardly as desired toincrease the length of the support. The retaining means is shown in Fig.4 in released position, wherein the collar 33 has been moved towards theouter end of the housing an amount suificient that the balls 35 nolonger contact with the beveled surface 28. In this position of thecollar 33 and the balls 3%, the rod I5 can be moved in either direction.The movement of the collar 33- .from locking to released position andvice verse:

is accomplished by a pair of pins 39 and ill mount-' ed on the rod 55with their ends projecting into the oppositely positioned grooves l3. InFig. 4, it will be observed that the rod i5 has been moved outwardly toa point where the spring band ii is in contact with a shoulder in thehousing 2! at the lower end of the peripheral surface 32. In thisposition of the rod 15, the pin M? is brought into contact with the lugs35 on the collar 33 and thus moves the collar outwardly an amountsufiicient to release the balls 35 from contact with the housing. Inorder that the collar 33 be moved to operative locking position,

it is then necessary to move the rod l5 inwardly until the upper pin 39contacts with the lugs 35 and returns the band to its original positionas shown in Fig. 3. The locking position of the retaining means isthereby obtained as described by moving the rod l5 inwardly the maximum1 allowable amount and the releasing position is obtained by moving therod outwardly the maximum allowable amount with the retaining means inlocking position. Obviously the length of the support can be extended inany desired amount up to the maximum by merely exerting a pull tendingto separate the upper and lower portions of the support, the retainingmeans meanwhile remaining in looking position and preventing anydownward movement. In the event it is desired to shorten the length ofthe support, this is accomplished pulling the rod i5 out the maximumamount and then moving the rod inwardly the maximum allowable amount andthen moving the rod outwardly to the desired point.

Fig. 2 illustrates a plurality of extensible supports as hereinbeforedescribed providing a mounting for an unattached stool, the members 62each being supported by a lug M as shown. Upper and lower cross braceshold the supporting members in fixed relation. The upper cross member $5is shown in Figs. 3 and l as clamped between the lower end of thehousing 2i and a shoulder on the upper end of the member l2. Stools ofthis character are portable and are generally carried from place toplace by grasping the seat iii. The frictional contact of the band iiwith the inner periphery of the member i2 permits the lifting of thestool in this manner without danger of the members is being pulledoutwardly.

In either of the stool constructions shown in Figs. 1 and 2, theadjustment of the height can be obtained with the stool in vertical orin any other position merely by exerting the necessary force tending topull the rod or rods l5 outwardly. The released position of theretaining means is accomplished in either construction by extending therods it the maximum allowable amount. The locking position of the rodsi5 is also obtained in either of the described constructions by pushingthe rod or rods inwardly the maximum amount as hereinbefore described.

An alternative form of retaining means is shown in Fig. 8 wherein isprovided a spring band P or collar 46 which is similarin all respects tothe spring band or collar 33 except that the balls (it are positioned incircular apertures 41 and a slightly modified form of housing 48 isused. The apertures i'l have inwardly diverging bounding walls wherebygravity seeps the balls in the apertures in contact with the rod iii.This embodiment of the invention is manipulated in the same manner forextending the rod l5 and for releasing the retaining mechanism ashereinbefore described in connection with the spring band or collar 33.

Still another form of retaining means is shown in Figs. 9, i and 11comprising a housing 56 of slightly larger diameter than shown for thehousings 2! and 48 already described. The housing 56 provides a chamber5! in which is mounted a collar E l having an annular flange 55. Thechamber 5i is bounded by downwardly converge ing side walls terminatingin a shoulder 52 and a cylindrical surface 85 of a diametersubstantially greater than that of the locking rod lb. The cylindricalsurface 55 terminates in a shoulder providing a support for a springband or sleeve 59 of a construction similar to the collar 33. The sleeve59 has a plurality of stems 59 projecting from its upper end contactingwith the flange 55 and thereby providing a support for the collar li t.The sleeve has a pair or oppositely positioned lugs 5'? positioned inthe grooves 53 of the rod iii. The groove 53 of the rod [5 is positionedadjacent one of the grooves l8 as best shown in Fig. and provides arunwayfior a key projecting from the collar E l. The spacing between thestems registers with the apertures and provides room for contact of theballs 3% with the rod I5.

The device is shown in Fig. 9 with the balls in contact with the housinglit, in which position the rod is locked against downward movement. ThisI" rm of the device is manipulated in the same manner as alreadydescribed for the embcdiments shown in Figs. 1 to 8, inclusive. Thedevice is released from locking position by moving the rod l upwardly toits maximum extended position, thereby bringing the pin 35 into Contactwith the lugs 5i and raising the sleeve 59 and the collar 5 against theresistance of the spring 38. The frictional contact of the sleeve towith the housing 55 prevents the spring 38 from moving the collar 54 andsleeve 59 downwardly when the d vice is in released position. The loweredges of the apertures 56 are inclined inwardly and downwardly thecollar 54 projects beyond the center of the balls 36 sufiiciently thatgravity tends constantly to hold the balls in contact with the rod 55when the device is in released position.

Thus it will be seen that I have provided an extensible supportingdevice for stools, and the like, and automatic locking means thereforwhich enables the supporting device to be extended any amount up to apredeterminedmaximum, the device being automatically locked againstinward movement at any intermediate position and released from lookingposition by extending the support its maximum amount, and is againreturned to locking position only upon complete retraction of thesupport.

Having thus described the invention, it is obvious that variousimmaterial modifications may be made in the same; hence I do not limitmyself to the exact form, construction and arrangement of parts hereinshown and described, or uses mentioned.

What I claim as new and. desire to secure by Letters Patent is:

1. An extensible member of the kind described comprising inner and outertelescoping members,

casing mounted on one end of the outer member and having a chamber withside walls converging towards the inner member,a collar having one endprojecting into the chamber and its other end in frictional contact withthe casing adjacent the small end of the chamber, said innermemberextending through said chamber and collar, the projecting end of saidcollar provided with a plurality of recesses, a plurality of ballbearings mounted one in-each of said recesses, means maintaining saidball bearings in their respective recesses in constant contact with saidinner member, means operable upon movement of said inner member to itsextreme inward position to move said collar to a position wherein theball bearings also contact'with said side walls, and means operable tomove said collar to a position wherein the ball bearings clear said sidewalls upon outward movement of said inner member to its extreme outwardposition.

' 2. In an adjustable stool having a seat, an extensible support for theseat comprising a lower member and an upper member telescoping withinthe lower, a casing on the upper end of the lower member having achamber bounded by downwardly converging walls, a collar frictionallyengaging the casing below and projecting into the chamber, said uppermember extending through said chamber and collar, said collar having aplurality of recesses in said projecting end, a plurality of ballbearings each mounted in one of said recesses in contact with said uppermember, means operable by inward movement of ber bounded by downwardlyconverging side walls,

a collar frictionally engaging the casing below and projecting into thechamber, said upper member extending through said chamber and collar,said collar providing a plurality of recesses in its projecting end, aplurality of ball bearings mounted one in each of said recesses incontact with said upper member, said upper member provided with meansfor moving the collar at substantially the end of the travel of theinner member in either direction, whereby said ball bearings arereleased from contact with said converging side walls when the uppermember is drawn to its extreme outward position and re main in releasedposition until the upper member has been retracted to the limit of itsinward movement, and means operable to move said collar to a positionwherein the ball bearings contact with said converging side walls uponretraction of said upper member to the limit of its inward movement.

4. In an adjustable stool having a seat, an extensible support for theseat comprising a. lower member and an upper member telescoping withinthe lower, a casing mounted on the upper end of the lower member andhaving a chamber bounded by downwardly converging side walls, a collarfrictionally engaging the casing below and projecting into the chamber,the upper member extending through said chamber and collar, a pluralityof ball bearings mounted in said chamber, said collar having a pluralityof recesses in its projecting end each providing a mounting for one ofsaid ball bearings, means maintaining said ball bearings in contact withsaid upper member, means operable by retraction of said upper member toits extreme inward position to move said collar to a position where saidball bearings contact with said converging side walls, and meansoperable upon movement of the upper member to its extreme outwardposition to move said collar to a position wherein the ball bearings aredisengaged from said side walls.

5. In an extensible construction, the combination of a supporting shaftmovable axially for adjustment, a retainer fixed in position andembracing said shaft and having an inner surface angularly arranged withrespect to said shaft, a free rolling member arranged between theangularly disposed face of the retainer and the presented face of theshaft and normally maintained contact with said faces so that movementof the shaft in one direction moves said free rolling member into wedgedlocking position to restrain movement of the shaft in said directionwhile permitting movement in the other, and means located within theretainer for moving said free rolling member to inoperative position topermit movement of the shaft in the first mentioned direction, saidshaft having a part for moving said means to release said free rollingmember at the end of the shaft movement.

6. In an extensible construction, the combination of a supporting shaftmovable axially for adjustment, a retainer fixed in position andembracing said shaft and having an inner surface angularly arranged withrespect to said shaft, a free rolling member arranged between theangularly disposed face of the retainer and the presented face of theshaft and normally maintained in contact with said faces so thatmovement of the shaft in one direction moves said free rolling memberinto wedged locking position to restrain movement of the shaft in saiddirection while permitting movement in the other, a sleeve arrangedbetween said retainer and said shaft and adapted to move in between theconverging faces of said shaft and retainer to move said free rollingmember out of locking engagement therewith, means operable by the shaftin its movement for moving said sleeve at the end of the shaft movementin each direction, and means holding said sleeve in assumed positions.

7. In an adjustable stool and the like, the combination of a tubularcasing having a chamber Whose interior walls converge downwardly, asupport slidably mounted in said casing, a free rolling member in saidchamber engaging its converging wall and the presented surface of saidsupport and adapted to be moved into wedged locking relation betweensaid wall and said support upon downward movement of said support,unlocking means relative to which said support is movable for liftingsaid free rolling member out of locking engagement with said support,and means on said support actuating said unlocking means as said supportis lifted to its upper limit to permit lowering of said support.

8. In an adjustable stool and the like, the combination of a tubularcasing having a chamber whose interior walls converge downwardly, asupport slidably mounted in said casing, a free rolling member in saidchamber engaging its converging wall and the presented surface of saidsupport and adapted to be moved into wedged locking relation betweensaid wall and said support upon downward movement of said support,unlocking means separate from said support for lifting and supportingsaid free rolling member out of locking position to permit lowering ofsaid support, and means operating as said support is moved to itsuppermost position for actuating said unlocking means.

9. In an adjustable stool and the like, the combination of a tubularcasing having a chamber whose interior walls converge downwardly, asupport slidably mounted in said casing, a free rolling member in saidchamber engaging its converging wall and the presented surface of saidsupport and adapted to be moved into wedged locking relation betweensaid wall and said support upon downward movement of said support, meansmounted for sliding movement in said casing for lifting and sustainingsaid free rolling member during lowering movement of said support, andmeans on said support operable at the end of its upward movement foractuating said sliding means.

19. In an extensible construction, the combination of a supporting shaftmovable axially for adjustment, a retainer fixed in position andembracing said shaft and having an inner surface angularly arranged withrespect to said shaft, a free rolling member arranged between theangularly disposed face of the retainer and the presented face of theshaft and normally maintained in contact with said faces so thatmovement of the shaft in one direction moves said free rolling memberinto wedged locking position to restrain movement of the shaft in saiddirection while permitting movement in the other, a sleeve arrangedbetween said retainer and said shaft, means operable by the shaft at theend of the movement of the shaft in one direction for moving said sleevein between the converging faces of said shaft and retainer to move saidfree rolling member out of locking engagement therewith, and meansoperable by the shaft at the end of the movement of the shaft in anopposite direction for moving said sleeve from between said convergingfaces and said shaft, to permit said free rolling member to move intolocking engagement with said shaft.

JAMES A. CAMPBELL.

